Dividend aligning mechanism



P 1953 G. w. HOPKINS 2,653,763

DIVIDEND ALIGNING MECHANISM Filed Dec. 22. 1948 6 Sheets-Sheet l v I n N X \\\\\\\\\\\\\\\\\\\\\\\\k\\\\\\\\\\\\\\\\\\\\\ y N s A 2 IN V EN TOR.

Sept. 29, 1953 G. w. HOPKINS 2,653,763

DIVIDEND ALIGNING. MECHANISM Filed Dec. 22. 1948 6 Sheets-Sheet 2 IN V EN TOR. 4

6 Sheets-Sheet 5 Filad Dec. 22. 1948 INVENTOR.

Spt. 29, 1953 G. w. HOPKINS 2,653,763

DIVIDEND ALIGNING MECHANISM Filed Dec. 22. 1948 6 Sheets-Sheet 4 IN V EN TOR.

Sept. 29, 1953 G. w. HOPKINS 2,653,763

DIVIDEND ALIGNING MECHANISM Filed Dec. 22, 1948 s Sheets-Sheet 5 IN V EN TOR.

Sept. 29, 1953 e. w. HOPKINS 2,653,763

DIVIDEND ALIGNING MECHANISM Filed Dec. 22. 1948 s Sheets-Sheet e F EEE 7 IN VEN TOR.

Patented Sept. 29, 1953 UNITED STATES PATENT OFFICE DIVIDEND ALIGNING MECHANISM George W. Hopkins, San Leandro, Calif., assignor to Friden Calculating Machine 00., Inc., a corporation of California Application December 22, 1948, Serial No. 66,777

12 Claims. 1

This invention relates to a division mechanism for calculating machines and more particularly to means for automatically aligning the dividend and divisor prior to the outset of a. division operation.

In performing division operations on calculating machines of the type having relatively s'hiftable dividend and divisor receiving devices, it has been necessary in the past for the operator of the machine to enter each of the factors in the machine and then to manually control the shift of the receiving devices relative to one another until the highest significant digits of the factors have been brought into alignment. The division mechanism is then set into operation by manipulation of a suitable control key or lever and the machine proceeds to divide the dividend by the divisor in a fully'automatic manner Without requiring any further attention on the part of the operator.

The present invention deals with a mecha nism for rendering the automatic division mechanism of a calculating machine more completely automatic by causing the dividend and divisor to be properly aligned prior to the outset of the division operation proper. According to the present invention, after the operator has set the dividend and divisor into the machine, the division key is depressed and the novel mechanism to be hereinafter disclosed causes the two factor receiving devices to be shifted relative to i one another until the highest order digits are brought into proper alignment for division after which the machine proceeds to automatically divide the dividend by the divisor and to indicate the result on a set of numeral wheels.

Hence, it is an object of the present invention to provide an improved automatic division mechanism.

Another object of the invention is to provide a mechanism for automatically aligning the dividend and divisor prior to the outset of the actual dividing operation.

A further object of the invention is to provide a dividend and divisor aligning mechanism which utilizes the existing automatic division mecha nism for effecting the alignment of the factors, the aligner mechanism merel serving to control the automatic division mechanism in such a manner as to cause the two factors to be properly aligned before the actual division operation takes place.

Still a further object of the invention is to provide a mechanism for aligning the dividend and divisor by causing continuous and repeated operation of the program control mechanism of the machine with right-hand shifting of the carriage until a tens transfer occurs in one of the higher orders of the dividend register. This condition then causes the continuous and repeated operation of the program control mechanism to be discontinued and conditions the machine for left-hand shifting of the carriage so as to cause a normal dividing operation to take place.

With these and other objects in View which will become apparent from the following description, the invention includes various novel combinations of parts and features of design which are incorporated in the preferred embodiment of the invention hereinafter to be described with reference to the accompanying drawings in which:

Fig. 1 is a longitudinal sectional elevation showing the basic mechanism of the machine.

Fig. 2 is a view showing those parts of the di vision control mechanism which are mounted on the left-hand side of the control plate.

Fig. 3 is a view showing those parts of the division control mechanism which are mounted on the right-hand side of the control plate.

Fig. 4 is a longitudina1 sectional elevation of the overdraft control mechanism located. on the left-hand side of the machine, this section being taken along the line 44 in Fig. 6.

Fig. 5 is a longitudinal sectional elevation showing details of the carriage shift reversing mechanism, this section being taken along the line 5-5 in Fig. 6.

Fig. 6 is a plan view showing the lateral arrangement of certain of the parts involved in the novel division aligner mechanism.

Fig. '7 is a front elevation of the carriage shift reversing mechanism.

The machine to be hereinafter shown and described is basically the same as the calculating machine shown in U. S. Patent No. 2,229,889, issued to Carl M. F. Friden, on January 28, 19%1, and hence, only so much of the mechanism shown and described in the aforesaid patent will be set forth herein as is necessary in order to provide a complete understanding of the manner in which the present mechanism is related to that shown in the patent. Similarly, the automatic division mechanism herein employed is essentially like that illustrated in U. 8. Patent No. 2,327,981, issued to Carl M. F. Friden, on August 31, 1943, and therefore only those parts of the automatic division mechanism which are directly coir cerned with the present invention will be disciosed in this application.

Selecting and actuating mechanisms As shown in Fig. l of the drawings the calculating machine is provided with a plurality of rows or banks of amount keys 2B which are mounted for vertical sliding movement by means of elongated slots 2! in the key stems which operate with through-rods 22 which are supported within the keyboard framework. The kevs 29 in each bank are resiliently urged into their raised. or undenressed positions by means of a longitudinally extending spring 23 which is threaded over the upper through-rods 22 and under studs 26 provided on the stems of the keys 2a. The lower ends of the key stems carry studs 2-5 which are adapted to cooperate with inclined cam faces 26 provided on selector bars 21. There are two such bars associated with each bank of keys and each of the bars is supported for horizontal reciprocating movement by means of a pair of parallel links 28 (only one shown in Fig. l) pivotally connected at their upper ends to the selector bars 2? and pivotally supported at their lower ends on rods 29 (only one shown) supported by angle bars at extending between a left side frame 3! and a right side frame 32 (Fig. 6) of the machine. The side frames 3| and 32 are suitably secured to a base 33 which also serves as a support for the covers 34 of the machine.

Each of the selector bars 2'! is urged toward the rear of the machine by means of a spring 35 tensioned between the lower end of each of the rear supporting links 28 and an angle-bar 36 extending between the side frames of the machine. At their rear ends, the selector bars of each pair are provided with bent-over, forked extensions 3'? which engage with grooves provided in the hubs of a pair of selector gears 38 which are slidably and non-rotatably mounted on a square shaft 39 which is journalled between cross-bars it and 3! extending between the side frames 3i and $2 and is also supported intermediate its ends by a bearing provided in an intermediate crossbar 42.

The selector gears 38 are arranged to cooperate with a drum type actuator 45 secured to an actuator shaft 46 which is journalled between the cross-bars tit and 12 and has secured to its forward end a bevel gear all which meshes with a bevel gear 63 secured to a transverse drive shaft 9. Secured to the actuator shaft 45 immediately behind the drum 45 is a second actuator drum 59 which is adapted to cooperate with a pair of selector gears controlled by an adjacent bank of amount keys 25.

As fully shown and described in the aforementioned Patent 2,229,889, the drums 45 and 50 are provided with a series of staggered actuator teeth which serve to rotate the selector gears 38 by differential amounts when the gears are slid forwardly on the shaft 39 into cooperative relationship with the teeth. As fully described in the patent, the 1-5 keys control the forward selector gear 38 while the 6-9 keys control the rear gear 38. When one of the 1-5 keys or one of the 6-9 keys is depressed, its associated selector bar 2? is moved forwardly by a differential amount through the cooperation of the stud with the inclined camming surface 25 so as to cause its associated selector gear 38 to be differentially positioned with respect to the actuator drum 45. The actuator teeth on the drum 45 will thereby rotate the selector gear 38 and the squa e 4 shaft 39 to an extent depending upon the value of the key depressed.

Slidably and non-rotatably mounted on the rear end of each of the square shafts 39 is a sleeve to which is secured an add gear 56 and a subtract gear 51, these gears being arranged to cooperate with a gear 58 secured to the lower end of a dial shaft 59 journalled in a hollow frame bar 60 of a shiftable numeral wheel carriage 68. Secured to the upper end of each of the dial shafts 59 is a numeral wheel 6! bearing the numerals from 0 to 9 which may be viewed through a window 52 provided in the casing 63 of the carriage.

The add and subtract gears 56 and 51 are normally maintained in a neutral position where they lie out of engagement with the gears 58, by a spring actuated centralizer 64 (Fig, 3) which yieldingly tends to maintain a gate shaft 65 (see also Fig. 1) in a neutral position. The shaft 65 is journalled at either end in the side frames 3! and 32 and has secured thereto a pair of spaced arms 55 (only one shown) which support a strap or gate 6'1 lying within the space existing between the add-subtract gears 56 and 57. When the gears 55 and 51 are located in their neutral position by means of the centralizer 6d, the numeral wheel carriage 68 may be shifted laterally across the machine without interference from the gears 56 and 5?. However, by means of a mechanism hereinafter to be described, the gate 61 may be moved rearwardly so as to engage the gears 55 with the gears 58 and, upon rotation of the actuator shafts 56, cause the accumulator wheels 6! to be rotated in a forward or positive direction.

Similarly, in subtract operations, the gate 51 is moved forwardly so as to cause the subtract gears 5? to mesh with the dial shaft gears 58 and thereby cause the accumulator wheels 6! to be rotated in a reverse, or negative, direction upon rotation of the actuator shafts 56.

Tens-transfer mechanism Secured to the lower end of each of the dial shafts 59 just above the gear 58 is a transfer cam l6 which is adapted to cooperate with a transfer lever 7! bearing a stud it? which is journalled in the carriage frame bar fit. Mounted on the outer end of the transfer lever ii is a pin '53 which lies between a pair of flanges provided on the hub is of a tens-transfer gear E5 located in the next higher order of the machine. The hub it and gear are slidably and non-rotatably mounted on the square shaft 39 whereby rotation of the gear 75 will be transmitted through the add-sub= tract gears 55, 57 to the dial shaft 59. When the accumulator wheel iii passes from 0 to 9 or from 9 to 0 a nose on th transfer cam it will rock the transfer lever ii and move the pin is forwardly so as to move the transfer gear 755 into the path of a single transfer tooth provided on a tens-transfer actuator '55 secured to the actuator shaft 45. Inasmuch as the pin it controls the transfer gear 75 in the next higher denominational order of the machine, the accumulator dial 6| in the next higher order will be advanced one step by the tens-transfer actuator 55 for this order thereby efiecting the carry from one order to the next higher order as required.

Revolutions counter Also provided in the numeral wheel carriage is a series of revolutions counter wheels each of which is secured to a longitudinally extending vshaft 8| journalled at its forward end in a carriage frame bar 82 and at its rearward end in the hollow cross-bar 66. Each of the wheels '86 is provided with a series of numerals from 8 to "9 which may be viewed through a window 85 provided in the casing 63 of the carriage. Secured to each of the shafts -8I adjacent to the wheels 80 is an actuator gear 84 which is 'arranged to cooperate with a revolutions counter actuator mechanism 85 so that with the numeral wheel carriage in its extreme left-hand position the right-most revolutions counter wheel 80 will be advanced one step for each rotation of the actuator shafts 45. This mechanism is fully shown and described in the above-mentioned Patent No. 2,229,889 to which reference may be had for a full and complete disclosure of this part of the machine.

Plus and minus keys In order to control the engagement of the add gears 56 with the gears 58 in th lower ends of the dial shafts or, alternatively, the engag ment of the subtract gears 5'! therewith, the machine is provided with a plus key 59 (Fig. 2) and a minus key 9!, both of which are slidably mounted on a control plate 92 spaced from secured to the right side frame 32 by suitable screws and spacing sleeves. The plus and minus keys are provided with roller studs 93 and 94, respectively, which cooperate with inclined can: faces 95 and 96, respectively, provided on a gate setting slide 91. Slide 91 is pivotally connected. at either end to the upper ends of arms 98 and NH (Fig. 3), the arm 98 being pivoted at 95} to the control plate 52 while the arm IN is secured to the gate shaft 55. Hence, when the plus key 923 is depressed, the gate setting slide 9? will be moved rearwardly so as to rotate the shaft in a clockwise direction thereby moving the gat (Fig. 1) toward the rear of the machine so to cause the add gears to be engaged with the shaft gears 58. In a similar manner, depression of the minus key SI, will, through the cooperaion of the stud 9 and the inclined surface 955, cause the gate setting slid 97 to be moved forwardly thereby rotating the gate shaft to counterclockwise so as to cause the subtract gears 52! to be engaged with the dial shaft gears 58.

For the purpose of initiating the cycling mechanism of the machine when either of the keys 9f! or BI .is depressed, each of these keys is provided with a half-round stud m which is adapted to cooperate with an inclined camrning surface I93 provided on a cycle initiating slide N34. The rear end of this slide bears against a pin H 5 which, when moved rearwardly, will cause the electric driving motor of the machine to be energized and the main clutch thereof to be engaged. This mechanism is shown and described in the aforementioned Patent No. 2,327,981 to which refor ence may be had for a more complet disclosure.

Carriage shift mechanism Means are provided for shifting the carriage in either direction from one ordinal position to another by power driven means controlled by manually operable shift keys. The power driven means is actuated by the two right-hand actuator shafts 46 in a manner which will be described more in detail hereinafter.

As shown in Fig. l, the numeral wheel carriage 63 has supported thereon a notched plate I I3, the notches in which are arranged to be engaged by a pair of shift pins I I I secured to the rear face of a carriage shift gear II2 journalled in the frame cross-bar 4|. For each one-half revolution of the gear 112, the carriage will be shifted one ordinal position so as to caus the dial shaft gears 53 to lie in cooperative relationship with the next actjacent set of add-subtract gears 56 and 5'2. In order to provide for accurate centering of the carriage at the end of a shift operation, a centralizing cam H3 is secured to the forward face of the shift gear I I2. Cooperating with the cam i I3 are apair of centralizing arms 5 I4 (Figs. 1 and 6) which are pivoted at one end to cross-bar 4i and provided on their opposite ends with rollers which engage with opposite sides of the cam H3 under the influence of a spring (not shown) tensioned between the arms I I4. When the pins 1 i i are in horizontal alignment as shown in Figs. 1. and '6, the carriage is properly located in one of its ordinal positions and the centralizing rollers are seated in opposite depressions formed be tween the high portions of the cam i it.

The shift gear I I2 is rotatable in either direction by selectively operable drive connections with the two right-most actuating shafts 46 of the machine. For this purpose these two shafts are extended rearwardly (Figs. 1 and 6) where each is provided with a collar I I5 secured to the rear end thereof. Each of the collars H5 is provided with a pair of diametrically opposite slots slidably engaged by a corresponding pair of teeth II 8 formed on a shiftable coupling member II! which is freely mounted on the ends of each of the shafts 46, Each member I I! is provided with a pair of oppositely disposed clutch teeth H8 which are designed to engage with corresponding slots provided in gear sleeves H9 and 823 rotatably journalled between the cross-bar All and a frame plate I2I secured in spaced relationship to the bar 4|. Gear sleeve II!) has mounted thereon a gear I22 meshing with an idler gear I23 (see Fig. 1) journalled between the bar ll and the plate IZI and meshing with the shift gear II2. Gear sleeve I20 has mounted thereon a gear I24 which lies out of the plane of the idler gear I23 and meshes with a wide reverse idler gear I25 suitably journalled between the bar AI and plate I2I. The idler gear I25 meshes with the idler gear I23 so that rotation of gear sleeve H9 in a clockwise direction, as viewed from the rear of the machine, will cause clockwise rotation of shift gear I I2 and thereby cause shifting of the numeral wheel carriage to the left as viewed from the front of the machine. Correspondingly, rotation of the gear sleeve I26 in a clockwise direction, as viewed from the rear, effects counter-clockwise rotation of the shift gear H2 and causes the numeral wheel carriage to be shifted to the right, as viewed from the front of the machine. Thus, by selectively establishing one or the other of the drive connections between the gear sleeves H9 and lid and the collars M5, the carriage may be shifted in either direction. The connection between the collars and gear sleeves may be selectively effected by shifting the members Ill rearwardly so as to establish a drive from the actuator shafts 48 to the carriage shift gear H2. The gear ratios are so chosen that one rotation of the actuating shafts 46 effects a degree rotation of the shift gear H2 and so causes the carriage to be shifted one ordinal space to the right or left.

As fully disclosed in U. S. Patent No. 2,327,635, issued to Carl M. Friden on August 24, 1A3, a pair of manually operable shift keys are provided for controlling the operation of the coupling members Hi. If the operator wishes to shift the carriage toward the right, this result may be effected by depressing the right shift key which causes a sleeve 529 (Fig. 1) rotatably mounted on a shaft I36 journalled between the right side frame 32 and a bracket i35 to be rocked counter-clockwise. This causes an arm i3l secured to the left end of the sleeve to enage with the forward end of a rearwardly extending rod E32 mounted for sliding movement in cross-bars 4i! and 42. The rod I32 is resiliently urged toward the front of the machine b means of a spring see compressed between cross-bar 48 and a suitable washer mounted on the forward end of the rod 32. At its rear end the rod is provided with a shift fork i3 3, the forked end of which engages with an annular groove provided in the right-hand coupling member Ill. Thus, when the sleeve 29 is rocked counter-clockwise, the arm as! will force the rod 132 rearwardly against the force of the spring I33 and thereby move the teeth lie on the coupling member Iii into engagement with corresponding notches provided in the gear sleeve i2i]. The rearward movement of the member ii? is insufiicient to cause the teeth lit to become disengaged from the slots provided in the collar H5 so that a positive driving connection is established between the actuator shaft to and the ear sleeve I26. As fully disclosed in the aforementioned Patent No. 2,327,635, depression of either of the shift keys causes the electric driving motor to be energized and the clutch to be engaged so that the actuator shafts 25 are rotated thereby causing shifting movement of the carriage in a righthand direction.

In a similar manner, depression of the left shift key will cause the shaft ltfi to be rocked coLmter-clockwise, as viewed in Fig. 1, thereby causing an arm secured to the shaft, similar to the arm Hi, to move a rod 35 (Fig. 6), similar to the rod 5 32, rearwardly in the machine thereby causing its associated shift fork 3? to move the left-hand coupling member iil rearwardly so that the teeth H3 thereof will engage with slots provided in the gear sleeve H9.

Automatic division mechanism As mentioned earlier herein, the machine shown in the accompanying drawings is provided with a mechanism for enabling a dividend set up on the accumulator Wheels SE to be automatically divided. by the method of successive subtraction by a divisor set up on the amount keys 2! As was mentioned above, the mechanism provided a in the present machine for accomplishing this purpose is similar to that shown in U. S. Patent No. 2.321981 and, accordingly, only the principal portions of the automatic division mechanism will be described herein.

The automatic division mechanism operates to control the functioning of the machine so as to cause the divisor to be repeatedly subtracted from the dividend until an overdraft occurs in the accumulator, whereupon the overdraft is corrected and the carriage shifted one ordinal space to the left where the process is repeated. The number of subtraction cycles effected in each order is registered in the revolutions counter as the quotient. The division operation is controlled by a program control mechanism which becomes effective each time an overdraft occurs in the accumulator to program the operation of the add-subtract mechanism and the carriage shift mechanism so as to cause a predetermined sequence of operation thereof during uninterrupted cyclic operation of the actuating mecha- Q as nism of the machine. The division operation is initiated by the depression of a division key which causes the program control mechanism to be operatively connected with the add-subtract gate and the carriage shift mechanism and renders the overdraft control mechanism effective to control the operation of the program control mechanism.

As shown in Fig. 2, a division key M5 is slidably mounted on the control plate 92 by means of elongated slots it provided in the key stem which cooperate with suitable guide studs i l? mounted in the control plate so as to guide the key for vertical reciprocatory movement. The key is normally urged to its raised position by means of a suitable spring 548 and is provided with an inclined cam face we which bears against a roller stud I50 mounted on a division control slide i5i. This slide is supported for endwise sliding movement on control plate as by means of elongated slots I52 which cooperate with studs I53 secured to the control plate. As shown in Fig. 3, the slide i5! is provided with a roller stud I54 which lies in front of a finger 555 formed on the upper end of a latch 56 pivotally mounted on the control plate 92 at 5? The finger IE5 is urged toward the front of the machine by means of a spring E58 tensioned between the lower end of the latch use and a stud 59 mounted in the control plate so as to normally maintain a shoulder 60 on the latch H56 beneath a stud iSi mounted on the forward end of a division setting actuator !52 which is pivotally mounted on a screw I63 fastened to the control plate 92. The actuator i 62 is urged to rotate in a counterclockwise direction by means of a strong spring we tensioned between the actuator and the stud 59 so as to urge the stud it! into engagement with the shoulder lei]. However, upon depression of the division key M5, the cam face his will engage with the roller stud use thereby moving the slide i5i rearwardly with the result that the roller stud i565 thereon will rock the latch I56 clockwise so as to remove the shoulder led from beneath the stud i5! and allow the actuator i 62 to be rocked counter-clockwise by the strong spring I64. The actuator will be restored during cycling of the machine by means of a roller I65 secured to the face of a gear 2% fast on the shaft 49. The roller 1% is adapted to engage an inclined cam face ass formed on an upwardly extending arm of the actuator thereby rocking the. actuator clockwise the urgency of the spring [6s and permitting the latch I56 to reengage with the stud i6! Lying beneath the forward end of the actuator l62 is a roller I68 (see also Fig. 2) mounted in the lower end of a link 159 which is pivotally connected at it! to the forward end of a connecting lever ill This lever is pivoted at ill to a follower arm H2 pivoted to the control plate at P13 and urged in a clockwise direction, as viewed in Fig. 2, by means of a spring lid. The armllz is provided with an aperture H5 within which is located an eccentric cam Hit secured to a program controlling shaft ill; As described in the aforementioned Patent No. 2,327,981, this shaft forms a part of the program control mechanism and is rotated during division operations to control the setting of the add-subtract gate and the operation of the left shift clutch. These operations are performed in a predetermined sequence so as to cause the machine to carry out a division operation in a fully automatic manner.

The lever I10 is provided at its rearward end with an upwardly directed arm I80 which is bifurcated at its upper terminus for the purpose of engaging with a stud I8I secured to the gate setting slide 97. Thus, when the division key I45 is depressed so as to release the actuator I62 (Fig. 3) for operation under the influence of its spring I64, the roller I93 will be carried downwardly, thereby causing the lever I10 (Fig. 2) to be rocked clockwise about its pivot I'II so as to engage the bifurcation with the stud IBI. When the control shaft II'I is in its normal or home position as shown in Fig. 2, the cam I16 thereon will cause the arm I12 to be maintained in its forward position, as shown in Fig. 2, so that when the lever H is rocked clockwise, upon depression of the division key, an inclined cam face I82 provided on the rear lip of the bifurcation will engage with the stud I8I and force the gate setting slide 91 into its forward position so as to engage the subtract gears with the dial shaft gears 58.

Mounted in the arm I86 is a half-round stud I85 which is adapted to be engaged by a springpressed latch 36 (Fig. 3) so as to retain the lever I is in its operated position throughout the division operation.

Pivotally connected to the upper end of the link I69 is the rearwardly directed arm of a bellcrank lever I99, which lever is pivotally mounted on a screw I9I secured to the control plate 92. The lever I90 has an upwardly extending arm which lies in front of a pin I92 mounted in the cycle initiating slide I 94. The bellcrank lever I99 is urged to rotate in a clockwise direction about the screw I9I by means of a spring I93 so as to normally maintain the link I69 in its raised position with the roller I68 engaged with the underside of the actuator I62 (Fig. 3) and also to maintain the lever no in the position shown in Fig; 2. However, when the division key is depressed, the link I69 will be forced downwardly by the strong spring I64 thereby rocking the bellcrank lever I90 counterclockwise and forcing the slide I04 rearwardly so as to operate the stud 165- and thereby cause-energization of the electric driving motor and engagement of the main clutch of the machine. 7

Referring now to Fig. 3 of the drawings, it

will be observed that the program control shaft HT extends through the control plate 92 and is provided on its righthand end with a mutilated gear I98 which is located in meshable relationship with a larger mutilated gear I99 which is secured to a conventional gear ace rotatably journall'ed on a screw ZQI mounted in the control plate 92. The gearZeQ meshes with the gear202 secured to the transverse drive shaft 49 so that when the main clutch is engaged and the shaft 49- rotated, the gear 202 will drive the gear 200 and the large mutilated gear I99. The small mutilated gear I93 is normally located in an inoperative position in which it lies out of the plane of the mutilated gear I522, such inoperative position being determined by a notch provided in the gear i953 engaging over a pin 263 on the control plate 32. The shaft IT! and the gear I 98 are normally urged to the left as viewed from the front of the machine by means of a compression spring (not shown) mounted on the leftdiand end of the shaft I'I'l' soas to urge the notch in the gear I98 to engage over the pin 203 in which position the gear lies out of the path of the large mutilated gear I99. As seen in Fig. 3-, gear I98 has three equally spaced sets of three teeth each for cooperation with a single set of two teeth provided on the gear I99. As the gear I99 rotates counter-clockwise during cycling of the machine, its two teeth are so positioned thereon as to engage one of the. sets of three teeth on the gear #98 immediately before the end of a machine cycle. Eencawhen the gear i923 is projected into the pathof the gear Hit during a cycle of operation of the machine, the gear 598 will be rotated clockwise through one-third of. a revolution at the end of that cycle and also through one-third of a revolution at the end of each of the two next succeeding cycles, the gear being maintained in its projected position by the engagement of the pin 203 with the inner face of the gear I98.

Mounted. on the lever I70 (Fig. 2) is a stud 2i I which lies beneath the forward end of an arm secured to a laterally extending shaft 2I3 which is journalled in the control plate 92 and the left side frame SI of the machine. Secured to the shaft 213 near the left-hand side of the machine is an arm 2I4 (Figs. 1 and 4) which bears a stud 2l'5 engaging in an elongated slot 2l6 provided in the lower end of an overdraft control link 2 I1. This link is pivoted at its upper end on a stud 2 I9 secured to a yoke 2 I 9 which is secured to an extension 229 provided on the highest order tens-transfer detent pin 22L As shown in Fig. 4, the pin 22 I is provided with a pair of flanges 222 which engage with. either side of one of the flanges provided on the hub 74 of the highest order tens-transfer gear l5 which is located on the leftmost square shaft 39'of the machine. As earlier mentioned herein, when a transfer is to be effected from a lower to a higher order, the transfer gear 15' is moved forwardly into the path of the single tooth provided on the tens-transfer actuator disc I6. Hence, when a transfer is effected which involves the shifting of the highest order transfer gear E5, th pin 22I will be moved forwardly thereby causing similar movement of the yoke H9 and the overdraft control link ZI'l pivoted. thereto. As shown in Fig. 4, the forward end of the link is normally held in its lower or inactive position by a spring 223 but, upon depression of the division key and rocking of the lever I10, the shaft 2I3 will be rocked clockwise, as viewed in Fig. 4, thereby lifting the forward end of the link 2|! so as to place an abutment face 224 formed thereon immediately behind a bail 225 which is pivotally but non-slidably mounted on the program control shaft I'Il. 'Ihe bail is normally held in a counter-clockwise position by means of a spring, 22"! secured thereto so as to maintain the rear end of an arm 223 formed thereon in contact with the under side of a sleeve 229 (Fig. 6) rotatably mounted on the shaft 253. When the forward end of the link 2i? has been moved. up behind the bail 22 5 upon the setting of the division mechanism and a' tens-transfer takes place which causes the highest order transfer gear 15 to be moved forward, the abutment face 224 will contact the bail 225 and cause it to be rocked clockwise about the shaft Ill against the urgency of the spring 22? so as to move a flag 232 formed on the bail into the path of travel of a pin 233secured-to a drum 234 on a shaft 466 which corresponds to the actuator shafts 46 with the exception thatthe actuators "i5 and 6d are omitted. Hence, as the shaft 469 rotates counterclockwise, as viewed from the front of the machine, the pin 233 will contact the flag 232 near the end of the machine cycle and force the shaft Ill to the right to thereby move the mutilated gear I98 into the path of its associated gear l99. Thus the shaft ill and the cam H6 (Fig, 2) will be given three steps of movement during the next three cycles of the machine after which the gear I98 will drop back over the pin 203 to its inactive position. The overdraft control link 2H will, meanwhile, be moved toward the rear of the machine so as to release the flag 226 as a result of the restoration of the detent pin 22! by the conventional tens-transfer restoring mechanism.

When the cam ii'fi occupies the position marked A in Fig. 2, which is the position of the cam when the notch in the small mutilated gear HM; engages with the pin 2%, clockwise movement of the lever ilii (Fig. 2) will cause the gate setting slide all to be moved forwardly and thereby engage the subtract gears 5'5 with the dial shaft gears 58. At the end of the subtract cycle in which an overdraft occurs, the shaft l'i'l will be rotated counterclockwise (Fig. 2) through 120 degrees to the position marked B. The rotation of the shaft and cam H6, in cooperation with the aperture H5, will cause the arm M2 to be rocked counter-clockwise, thereby moving the lever lid toward the rear of the machine so as to cause the add-subtract gate to be moved to its add position. During the next cycle of the machine, the divisor set on the amount keys 2%] will be added back into the accumulator so as to correct the overdraft and at the end of this cycle the shaft Ill will be rotated through another 120 degrees to the position marked and thereby move the arm 112 to an intermediate position where the add-subtract gears 56 and will be held out of engagement with the dial shaft gears 58 preparatory to a carriage shifting operation. The arm H2 will be yieldably maintained in this intermediate position by means of a spring-urged centralizer arm 288 which is provided with a v-shaped nose which is adapted to engage in a corresponding notch provided in the upper edge of the arm H2.

In order to cause the carriage to be shifted one ordinal position to the left, that is, in the direction of increasing orders, during the machine cycle following movement of shaft IT! to position C, a cam 2% (Fig. 6) provided with an actuating nose 25! is secured to the shaft ill just within the right side frame 32 of the machine. When the shaft ill is moved toward the right by the action of the pin 233 on the flag 226, the cam its is moved toward a follower arm 2 32 (see also Fig. 7) which is secured to a sleeve 233 mounted on a transverse shaft 244. This shaft is journalled at its right-hand end in the side frame 32 and at its left-hand end in a bracket 2 55 secured to the frame cross-bar 42. The sleeve 2% is slotted as shown at 286 so as to receive a key E li secured to the shaft 2% whereby the sleeve may be moved axially along the shaft 244 but any rocking movements of the sleeve will be transmitted to the shaft. The sleeve is provided with a flange 2&8 which, together with the follower arm 242, provides an annular groove within which is received a finger 249 provided on a bellcrank lever 25%. This lever is pivotally mounted on a stud 25! mounted in a bracket 252 which is riveted to the right side frame 32. The bellcrank lever is provided with a bent-over extension 253 which lies over the left-hand end of the stud 2!! carried by the lever liil (see Fig. 2). Hence, when the division key is depressed and the lever H6 rocked clockwise, as viewed in Fig. 2, the pin ill will be elevated so as to rotate the bellcrank 258 counter-clockwise, as viewed in Fig. 7, thereby moving the sleeve 253 and follower arm 242 to the left against the opposition of a compression spring 25 situated on the shaft 2 54. Referring again to Fig. 6, this movement of the follower arm 2 32 by the pin 2i i is such as to bring the follower arm into the plane of the nose 24H on the cam when the shaft ii? occupies its active or right-hand position. The radial positioning of the nose 2 on the cam 246 is such that when the shaft ill is moved from position B to position C, the cam will rock the follower arm 2&2 clockwise, as viewed from the left-hand side of the machine, thereby causing the shaft 2s to which the sl eve 2 33 is keyed to be similarly rocked. This will cause the left shift clutch to be engaged, through mechanism later to be described, and thereby cause the carriage to be moved one ordinal space to the left.

The calculatin machine is normally provided with a counter reversing key 258 (Fig. 3) which lies beside the division key Hi5 and is normally depressed along with the division key when a division operation is initiated.

Depression of the key 253 causes the revolutions counter to be operated in a reverse or negative direction thereby causing the subtraction cycles occurring during a division operation to be counted in a positive sense. The mechanism for accomplishing this result is indicated generally at 25s in Fig. 3 and for a complete disclosure of this part of the machine attention is invited to U. S. Patent No. 2,294,111 granted to Carl M. F. Friden on August 25, 1942.

A division operation may be terminated at any stage of the proceedings by means of a manually operable stop lever (not shown) which serves to release the latch 986 from the pin 3S5 thereby allowing the connecting lever we to return to its normal, inactive position as shown in Fig. 2. The slide it will thus be released and the motor will stop. The division stop lever and its associated mechanism is fully shown and described in Patent No. 2,327,981, supra.

Automatic division aligner At the conclusion of a division operation the numeral wheel carriage of the calculating machine is normally located in its extreme lefthand position and it is then necessary for the machine operator to shift the carriage to the right until the highest order digits of the dividend and the divisor are brought into proper alignment for a division operation. In order to render this operation automatic and to relieve the operator of the necessity of controlling the shift of the carriage until the dividend and divisor are properly aligned for the performance of a division operation, the mechanism hereinafter to be described has been provided. In the use of the machine embodying this mechanism, the dividend is entered in the accumulator inboard with respect to the transfer detecting stud member are. This mechanism makes use of the previously described division program control mechanism, the normal operation of this mechanism being suitably modified so as to cause the carriage to be automatically tabulated to the right until the factors are properly aligned, after which an automatic division operation will automatically take place. For this purpose a link 300 (Fig. 3) is pivotally connected at its forward end to the actuator H62 and at its rear end to an arm sill secured to a cross-shaft 362 journalled between the side frames of the machine. Hence, when the division key M5 is depressed and the actuator I62 released for counter-clockwise rotation under the influence of the heavy spring 64, the shaft 302 will be rocked counter-clockwise. As seen in Figs. 4 and 6, the shaft 302 has secured thereto a forwardly directed arm 303 which is provided at its forward end with a stud 304 which lies above the forward end of an arm 335 secured to a sleeve 306 journalled on the shaft 213. Thus, when the shaft 3&2 is rocked counter-clockwise, the stud 304 will contact the arm 365 and cause this arm and the sleeve 336 to also be rocked counterclockwise. The sleeve 306 is clutched at 30'! (Fig. 6) to the sleeve 229 which has secured thereto an arm 308 (Figs. 1 and 4.) provided at its rear end with a bent-over ear 333. This ear is adapted to cooperate with a latch 3l0 loosely pivoted on the gate shaft 65, the latch being urged into engagement with the ear by a spring 3!! tensioned between the latch and the arm 308. Upon counterclockwise movement of the sleeve 229, the ear 309 will be engaged by the latch 3 l so as to maintain the sleeves 229 and 306 in their rocked positions.

Also secured to the sleeve 306 is a disc cam 3l5 (Figs. 5, 6 and '7) which is provided with a series of four inclined cam faces 3l6 which cooperate with a four-pointed cam follower 3 l l which is secured to a sleeve 3I9 journalled on the shaft 2 l3. On the right-hand end of the sleeve M8 is secured a shift fork 3l9 which engages with an annular groove 323 provided in a selector clutch element 328 which is slidably keyed to the shaft 243. The member 32I is provided on its righthand end with clutch teeth 322 and on its left-hand end with clutch teeth 323 (Fig. 7) which are adapted to engage with corresponding notches 324 and 325, respectively, provided in collars 323 and 32! of a right shift clutch engaging arm 328 and a left shift clutch engaging arm 329. The collars 326 and 32? are rotatably mounted on the shaft 244 but are held against axial displacement therealong by means of set screws 330 which are threaded into the collars and engage with grooves 331 provided in the shaft 244. As shown in Fig. 6, the cam follower 3|! is normally seated in the bottom of the notches provided in the cam 3l5 as a result of the action of a compression spring 335 located on the shaft 2l3, this spring bearing at one end against the shifter fork 319 and at the other end against a collar fastened to the shaft 2l3. When the parts are positioned as shown in Fig. 6, the clutch member 22f is in its left-hand position wherein the teeth 323 (Fig. 7) thereon engage with the notches 325 provided in the collar 32? on the left shift engaging arm 329. Hence, when the shaft 264 is rocked by the program control mechanism, the arm 329 will be operated (see also Fig. so as to move the shifting fork I31 for the leftshift clutch rearwardly and thereby cause the carriage to be shifted one ordinal space to the left. However, when the sleeve 303 is rocked counter-clockwise, as previously described, the inclined cam faces (M6 on the cam 3l5 will force the sleeve 318 to the right against the opposition of the spring 335 thereby disengaging the teeth 323 on the member 32| from notches 335 and engaging the teeth 322 with the notches 323 in the collar 326 of the right shift engaging arm 323. Hence, when the shaft 244 is rocked by the cam 24% during operation of the program control mechanism, the right shift clutch will be engaged so as to cause movement of the carriage to the right.

In order to cause operation of the program control mechanism to take place immediately upon the initiation of a division operation, an arm 340 14 (Fig. 6) secured to. the sleeve 229 is provided with a pin 34! which overlies the rearward extension 228 (Fig. 4) of the flag 226. Hence, upon the rocking of the sleeve 229 upon the initiation of a division operation the flag 226 will be rocked clockwise against the action of the spring 221 so asv to move the flag 232 into the path of the pin 233 and thereby cause the program control shaft H1 to be moved to the right into its operative position. The program control mechanism will function as in the case of a division operation with the exception that the carriage will be shifted one ordinal space to the right for each rotation of the shaft Ill instead of to the left as in a conventional division operation. Hence, the carriage will be moved to the right, that is, in the direction of decreasing orders, to cause the highest digits of the dividend and divisor to be brought: into alignment. By virtue of the latch 3|0 (Fig. 4) which maintains the sleeves 223 and 306 in their rocked positions, the program con trol mechanism will be maintained effective and the right shift clutch will be conditioned for operation so long as the latch remains in engagement with the ear 309.

In order to terminate the shifting of the carriage to the right. once a dividend and divisor have been properly aligned for a division operation, the latch 3 l 0 is provided with an upwardly extending tail 345 which lies in front of the pin 228 connected with the transfer detent pin 22I. Upon the occurrence of a tens-transfer involving the transfer gear I5 to which the detent pin H8 is connected, the pin 2l8 will move forwardly so as to engage the tall 345 and disengage the latch 310 from the ear 3539 whereupon the spring 3 will rock the sleeves 223 and 306 clockwise as viewed in Figs. 1 and 4. The tens-transfer will normally occur as the result of an overdraft in the accumulator dials 6! whereupon the higher order dials will move from 0 to 9 and hence cause a transfer to be effected which will cause the latch 310 to be disabled. The overdraft in the accumulator will occur during the subtraction cycle of the subtract, add-back and shift proram. enforced by the program control mechanism once on each revolution of the shaft I'll. Thus, when the carriage has been moved sufficiently far to the right to locate the highest digit in the divisor to the left of the highest digit in the dividend, or when the highest digits of the factors are brought into alignment and the divisor is larger than the dividend, an overdraft will result during the subtraction cycle which will trip the latch 310 and permit the sleeves 229' and 336 to be returned in a clockwise direction under the influence of the spring 31 I. Upon the restoration of the sleeves 229 and 306 to their normal positions, the pin 34] will release the flag 226 and the clutch 32! will be moved to the left by spring 335 so as to condition the left shift clutch for operation by the program control mechanism. The machine will now be controlled by the conventional automatic division mechanism operating in its normal manner to cause a left-hand shift of the carriage each time an overdraft occurs. As previously stated, an overdraft causes the transfer detent pin Hi to be moved forward and the flag 232 to be rocked by the forward end of the link 21'! thereby causing the shaft H! to be moved to the right in order to initiate a cycle of operation of the program control mechanism.

As set forth in Patent No. 2,327,981, the latch [86 (Fig. 3) is disabled by a pawl on the carriage when the carriage reaches its extreme lefthand position thereby terminating the division operation. Hence, in the machine shown and described in the patent, a subsequent division operation cannot be initiated with the carriage in its lowest order position since the latch is held out of engagement with the stud I8l. In the present machine, however, means is provided for disabling the pawl on the carriage when the division key is depressed so as to enable the connecting lever l'iil to be retained in its operative position by the latch I85 regardless of the position of the carriage.

As shown in Figs. 2 and 6. a pawl 350 mounted on the carriage serves to disable the latch I86 when the carriage reaches its extreme left-hand position. This pawl is provided with an arm 35I bearing a pin 352 which is adapted to be engaged by a shoulder formed on the rear end of a pawl 353 pivoted on a screw 354 fastened to an extension 355 provided on the rear end of an interlock slide 356. This slide carries a stud 351 which lies just behind the cycle initiating slide Hi l so that when the latter slide is moved toward the rear of the machine when the division key is depressed, the slide 356 will be carried rearwardly along with it. Hence, the shoulder on the pawl 353 will engage the pin 352 and rock the pawl 35!! counterclockwise (Fig. 6) against the tension of a spring 358 so as to release the latch I86. The pawl 353 is made yielda'ble so that it may give way when contacted by the pin 352 as the carriage moves into its leftmost position with the slide 355 in its rearward position. This is accomplished by means of a spring 359 which normally holds a formed-over ear 369 on the pawl in engagement with the edge of the extension 355, the spring 359 being made somewhat weaker than the spring 358. Hence, the spring 359 will be overcome by the spring 358 and allow the pawl 358 to terminate the division operation when the carriage returns to its lowest order position at the end of a division problem.

A rule of operation of the machine disclosed caused by a zero intervening between outboard significant dividend figures standing to the left of the detecting member 2 l 8.

Operation The novel factor aligning mechanism hereinbefore described operates as follows:

When any given number is to be divided by any other given number on the present machine, the operator first enters the dividend into the accumulator wheels 6! with the dividend figures inboard of the detecting member 2I8, no significant dividend figure being in a higher ordinal position than the member ZIB. The dividend may be entered by setting this figure on the amount keys 2i} and depressing the plus bar 90 so as to give the machine a single cycle of operation and thereby cause the amount to be entered into the accumulator wheels in a posii6 tive sense, or the dividend may be entered into the wneels SI by means of the twirler knobs normally provided on the upper ends of the numeral wheel shafts 59 for this purpose. The dividend having been entered into the wheels 6! and the revolutions counter wheels 86 having been zeroized, the operator then sets the divisor on the amount keys 20 and depresses the division key I 35 so as to trip the division setting actuator I62 (Fig. 3) and cause the sleeves 229 and 306 to be rocked counter-clockwise where they will be held by the latch 3" This causes the clutch member 32I (Fig. 6) to be moved to the right so as to condition the right shift clutch for engagement and also causes the flag 232 to be rocked into operative position. At the same time, the overdraft control link 2 N (Fig. 4) will be raised into position behind the bail 225 so as to enable conventional control of the program control mechanism during the actual dividing operation which follows immediately after the factors have been properly aligned. When the division key M5 is depressed, the electric driving motor will be energized and the main clutch engaged in the well-known manner so as to initiate cycling of the main operating mechanism of the machine. Since the flag is maintained in operative position by the pin 3 .1, the program control mechanism will be effective to cause subtract, add, and right shift cycles to automatically take place, the carriage being moved one ordinal space to the right for each complete revolution of the mutilated gear I98 (Fig. 3). The machine will continue operating in this manner until the carriage has been shifted sufficiently far to the right to cause the highest digit in the dividend to be positioned one ordinal space to the right of the highest digit in the divisor whereupon an overdraft will occur in the accumulator dials BI thereby causing the latch am to be tripped and the division aligner mechanism to be restored to its original, or inoperative, position. When this occurs, the flag will be released by the pin 3M and the clutch member 32I will be moved to the left so as to condition the left shift clutch for engagement whereupon a conventional automatic division operation will ensue. During division, the divisor will be subtracted from the dividend a sufficient number of times to cause an overdraft to occur in the higher order wheels of the accumulator whereupon the link 2| 7 (Fig. 4) will be moved forward so as to rock the flag into operative position to cause cycling of the program control mechanism. This will result in adding back the divisor so as to correct the overdraft; then a left shifting movement of the carriage so as to translate the dividend one ordinal space to the left with respect to the divisor set up on the keys 2d; and finally the setting of the gate for subtraction. The divisor will then be subtracted from the dividend until an overdraft again occurs in the accumulator dials which will cause the flag to again be set into operative position and again causing cycling of the program control mechanism to be initiated. This operation will be continued until the carriage has reached its extreme left-hand position whereupon the lever Ilii (Fig. 2) will be released from the latch I86 (Fig. 3) so as to terminate the division operation and stop cycling of the machine. The machine is now ready for another division operation in which the dividend is entered int t accumulator wheels and the divisor is set-up on the keyboard after which the division key is depressed so as to again set the division aligner ,1? mechanism nto .flps e' 'i e in vi s 4d?- scribed and cause" righthand shiftingbf jthe carriage until thefactor's are aligned, after which the conventional automatic division mechanism ,will take over eontrol of the machine and "cause the dividend to be divided by the divisor iiia fully automaticmanner. i

Iclaim: 1. In a calculating machine of the class described having a keyboard in which thedigits", of

a divisor may be set, a shiftable carriage, register insaid carriage in which theidigits'of a dividend may beset, means for shiftiiigsai d carriage in, one, direction or another with respect to of successive subtraction, said means iilclud i a manually controlled nechanism for initiating a division operation, wmeans at the higher orderend of said keyboard andactuatingmeansfor detecting thev occurrence of a tens-transfer in the higher orders of, said register, and acyclically operable programmingdevice forautomatically controlling the sequential operation of said i actuating means and said carriage shiiting vmeans; means forsetting a dividend in said registerinboard of saidjdetecting means with no si nificant figure. ofsaid dividend beingina higher ordinal position than ,said de tect ing means; a settable device operable by, said tens transferdetecting means for causingan operation ofsaid programming device. to beeinitiated therebycausing positive actuationnof" said register, shifting of the carriage and negative, actuation of the register, auxiliarycontrol mechanism operable by said manually controlledmechanism for causing saidsettabledeviice to, be operated and said carriage shifting. means to ,be conditioned, to

the control of said tens-transfer detecting means .and causing said carriageshiftingmeans tobe conditioned to shift the register in the direction :of increasing orders of said register.

2. In a machine of the class described having; 55 a keyboard on which the digits of a divisor, may

be set, a shiftable carriage, a. register in said carriage on which the digits ofv av dividend may be registered, means for actuating said register in accordance with the amount set on; said keyboard, means for shifting said carriage ,in one direction or another withrrespect ,toisa'idkeyboard, said means includinga' right shift clutch and a left shift clutch and means for engaging one or the other of said clutches, said means;

vbeing-normally conditioned to engage said left shift clutch, 'means at the higherorder end. of said keyboard for detecting a tens-transfer in dividend figure being in a higher ordmal'posi- 7 tion than said detecting mezinstheboihbination f means for dividing said dividend byadivisor set in said keyboard'including a manually. con

trolled mechanismjor initiating a division operj'ation, and a cyclically operable programming fdevice normally operated by' said tens-transfer 'fdetecting deviceforcontrolling the operation of said actuating meansand said clutch engaging means: a" normally inoperative factor aligning device for causing continuous'and'repeated operation'of saidprogramming device and for con- "jditioning isaidflengaging means to engage said 10 "'rightfshiftclutch; means operated by said manu- "ally controlled" mechanism for rendering said "factor aligningd'eviceoperative; and means contioll'ed'by said'tens-transfer detectin means for rendering said device inoperative When a transjfer'jfoccursin one of the higher orders of the fregisterith'ereby' disabling the continuous and repeated foperation of 1 said programming device 'aiidcausing saidengaging means to be condioned to'engage said left shift clutch.

ajcal'culatingmachine of the class describ'edhavingfa value entering means for re- :cei'vingthe' divisorjfactor of a division problem, a register for receiving the dividend factor, means 'for'transmitting the divisor factor from 5'said value entering means into said register, and

means for shifting said register relative to said 'valu'e entering means, the combination of means for automatically dividing the dividend by the divisor including a'member movable from an idle d'positionto an active position, means for initiat- "ing operation of said dividing means and for moving said member'from its idle position to its active position; means for retaining said mem- 'ber in itsfactive positionthroughout a division joperati0nf means for causing said retaining ineans to be disabled at the end of a division operation; and means operated by said initiating means for disabling said last-named means so as to render said retaining means again effective 5f to'hold said member in its active position.

shift the register in the direction,ofldecreasing flcarriageiforreceiving the divldend factor means orders of saidiregister; and meanscontrolled by .said tens-transfer detecting, means for disabling .said auxiliary control mechanism when atrans- .fer occurs in one of. the higher orders of said 0 i register thereby placing said settabledevice under 0 imovable irom. an 1 d1 8 posltmn to an active p Ii for transmitting the divisor factor from said val ief entering means into said register, and

means. for shifting said carriage, the combina- "T'tionjof means for automatically dividing the dividend by the divisor including a member i'tion, means, including a manipulative member, 'for' initiating operation of said dividing means j and for moving'said member from its idle posi- "tion'to its active position; means for retaining said member in its active position throughout "a division operation; means movable in accordance withthe movement of said carriage for causing said retaining means to be disabled in a predetermined position of said carriage; and

"means operable upon movement of said manipulative' member for disabling said last named means so as to render said retaining means once f more effective to hold said member in its active position.

5. In a calculating machine of the class describedhaving a value entering means for re value entering means into said register, and means for shifting said carriage, the combinaftion of 'means for "automatically dividing the dividend by the including a member movable from an idle position to an active position, means, including a manipulative member, for initiating operation of said dividing means and for moving said member from its idle position to its active position; a latch for retaining said member in its active position; a device mounted on said carriage for causing said latch to be disabled in a predetermined position of said carriage; and means moving in response to movement of said manipulative member for disabling said device so as to render said latch once again efiective to hold said member in its active position.

In a calculating machine of the class described having a value entering means for receiving the divisor factor of a division problem, a shiftable carriage, a register mounted in said carriage for receiving the dividend factor, means for transmitting the divisor factor from said value entering means into said register, and means for shifting said carriage, the combination of means for automatically dividing the dividend by the divisor including a member movable from an idle position to an active position, means, including a manipulative member, for initiating operation of said dividing means and for moving said member from its idle position to its active position; a latch for retaining said member in its active position; a latch-disabling pawl mounted on said carriage, said pawl being movable into engagement with said latch so as to disable the same in a predetermined position of said carriage; and means controlled by said manipulative member for moving said pawl out of engagement with said latch when said member is manipulated thereby enabling said latch to once again hold said member in its active position.

'7. In a calculating machine of the classrdescribed having means for giving the machine cycles of operation, a frame, a plural order amount entering means on said frame for receiving the divisor factor, a plural order register for receiving the dividend factor, means for shifting said register ordinally relative to said amount entering means, a tens-transfer mechanism for said register, a detecting member mounted on said frame at the higher order end of said amount entering means for detecting a transfer in an order of said register ordinally aligned with said detecting member, and means for entering the value in said amount entering means in said register inboard of said detecting member additively or subtractively, the combination of a division control mechanism controlled by operation of said detecting member for operating the value entering means and the shifting means to cause the divisor factor to be subtracted from the dividend factor and the register to be shifted intermittently to the left during continuous, uninterrupted cycling of the machine; means for modifying the control of said division control mechanism so as to cause said shifting means to shift said register to the right in sequential cycles of operation; and means controlled by said detecting member for disabling said modifying means when a transfer occurs in an order of said register aligned with said detecting member so as to enable said shifting means to again shift said register to the left and to restore control of said division control mechanism to said detecting member.

8. A calculating machine capable of carrying out problems in division comprising a value indexing means in which the various digits of a divisor maybe set; a carriage mounted for endwise shifting movement on said machine; a register comprised of a plurality of ordinally arranged numeral wheels rotatably mounted on said carriage, some of said wheels lying inboard with respect to said value indexing means and others lying outboard thereof, said wheels being settable to represent the various digits of a dividend; a tens-carry mechanism for transferring a unit from a lower order register wheel to' a higher order register wheel; a detecting member at the higher order end of said value indexing means for detecting a tens-carry in a numeral wheel of said register aligned with said detecting means; means for entering the dividend .in said register inboard of said detecting member with no significant figure of said dividend being in a higher ordinal position than said detecting member; means for successively subtracting the divisor from the dividend, adding the divisor to the dividend, and shifting said carriage one step to the right in sequence so as to bring the higher order inboard wheels of said register into active position with respect to a divisor value set in said value indexing means; and means controlled by said detecting member for terminating the operation of said shifting means to the right when the dividend and divisor are correctly aligned for the performance of a division operation.

9. In a calculating machine of the class described having plural order value indexing means, a plural order register shiftable relative thereto, means adjacent the higher order end of said value indexing means for detecting a tenstransfer in an order of said register which is ordinally aligned with said detecting means, a plural order differential actuating means for entering a value set in said indexing means into said register inboard of said detecting means, and means for shifting said regis' er, the combination of a division mechanism for controlling the operation of the machine in division operations, including means controlled by said detecting means for operating said differential actuating means and for intermittently operating said shifting means for shifting said register in such a direction as to bring the lower orders thereof into alignment with said value entering means, manual means for initiating operation of said division mechanism, aligning means associated with a said manual means and operated therewith for temporarily modifying normal operation of said division mechanism by said detecting means to cause said actuators to be operated and said register to be shifted cyclically in such a direction as to bring the higher orders thereof into alignment with said value entering means; and means controlled by said tens-transfer detecting means for disabling said aligning means when a transfer occurs in the order of said register aligned with said detecting means to thereby enable said division mechanism to control the operation of the machine in the normal manner.

10. In a calculating machine of the class described having a plural order keyboard, a plural order register shiftable relative thereto, egister shifting means, differential actuator means for entering the keyboard factor into the aligned orders of said register additively or subtractively, an overdraft sensing means adjacent the higher order end of said differential actuator means, a normally inoperative division mechanism for controlling the operation of the machine to divide a dividend registered in the register by a divisor set in the keyboard, said mechanism including means operated by said sensing means for controlling operation of said actuator means to cause the divisor to be subtracted from the dividend repeatedly to an overdraft and for thereafter operating said register shifting means to shift said register in such a direction as to bring the lower orders thereof into alignment with said keyboard, and a manipulable member for rendering said division mechanism operative; the com bination of aligning means controlled by said manipulable member for modifying normal operation of said division mechanism by said sensing means to cause operation of said differential actuator means to subtract the divisor from the dividend once and for modifying normal operation of the register shifting means to shift the register in the opposite direction in repetitive sequence in order to bring the higher orders thereof into alignment with said value entering means; and means controlled by said overdraft sensing means for disabling said aligning means and to enable said division mechanism to control the normal operation of the machine under con trol of said sensing means.

11. In a calculating machine adapted to perform division by the successive subtraction method comprising a plural order keyboard; a plural order register shiftable relative thereto; differential actuating means operable to transmit a value set in said keyboard into said register; and overdraft detecting means adjacent the higher order end of said differential actuating means; a reversible shifting means for shifting said register including a left shift clutch, a right shift clutch, an initiating member operable to cause engagement of either shift clutch, and means for selectively conditioning said initiating member to operate either of said clutches; means for resiliently biasing said initiating member to a position in which it is conditioned to operate said left shift clutch; a division mechanism for controlling the operation of said differential actuating means and said shifting means in division operations including means controlled by said overdraft detecting means for operating the differential actuating means subtractively to an overdraft and thereafter operating said initiating member; a manipulable member for controlling the operation of said division mechanism; means controlled by said manipulable member for moving said initiating member to the position in which it is conditioned to operate said right shift clutch and for cyclically operating said overdraft controlled means; and means controlled by said overdraft detecting means for releasing said member to said biasing means and for terminating cyclic operation of said overdraft controlled means when a transfer occurs in one of the higher orders of the register.

12. A calculating machine for performing division operations comprising a frame, a shiftable carriage on said frame, a plurality of ordinally arranged register wheels mounted on said carriage in which may be registered the dividend factor, a plural order selection means for receiving the divisor factor, a plural order differential actuating means, a tens-transfer mechanism for transferring a unit from a lower order register wheel to a higher order register wheel, a detecting member movably mounted on said frame adjacent the higher order end of said selection means for detecting a transfer in a register wheel ordinally aligned with said detecting member, means for shifting said carriage ordinally including a movable device settable in one position for causing said carriage to be shifted to the right and settable in another position for causing said carriage to be shifted to the left, an intermittently operable division program mechanism controlled by said detecting member, a division initiating key, auxiliary means cooperating with said key for moving said device to said one position and for initiating a cyclic operation of the division program mechanism to cause operation of the machine in the steps of a single subtraction, a single addition, and operation of the carriage shifting means; and means controlled by movement of said detecting member when it detects a transfer in a register Wheel aligned with said detecting member for disabling said auxiliary means and moving said device to said other position.

GEORGE W. HOPKINS.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 2,327,981 Friden Aug. 31, 1943 2,365,507 Allen Dec. 19, 1944 2,408,097 POtt Sept. 24, 19-46 2,416,809 Avery Mar. 4, 1947 

